diff --git a/os/ports/RVCT/ARMCMx/chcoreasm_v6m.s b/os/ports/RVCT/ARMCMx/chcoreasm_v6m.s
index 2091577ef..0c6e33260 100644
--- a/os/ports/RVCT/ARMCMx/chcoreasm_v6m.s
+++ b/os/ports/RVCT/ARMCMx/chcoreasm_v6m.s
@@ -88,10 +88,10 @@ _port_switch_from_isr PROC
                 bl      dbg_check_lock
 #endif
                 bl      chSchDoReschedule
-_port_exit_from_isr
 #if CH_DBG_SYSTEM_STATE_CHECK
                 bl      dbg_check_unlock
 #endif
+_port_exit_from_isr
                 ldr     r2, =SCB_ICSR
                 movs    r3, #128
 #if CORTEX_ALTERNATE_SWITCH
diff --git a/readme.txt b/readme.txt
index 42fbb8349..9207188e7 100644
--- a/readme.txt
+++ b/readme.txt
@@ -81,6 +81,8 @@
 *****************************************************************************
 
 *** 2.5.0 ***
+- FIX: Fixed problem with arm-v6m and state checker (bug 3532591)(backported
+  to 2.4.2).
 - FIX: Fixed wrong MAC divider setting in STM32 MAC driver (bug 3531290)
   (backported to 2.4.2).
 - FIX: Fixed wrong MCO1 divider in STM32F2/F4 HAL (bug 3531289)(backported